1. Field of the Invention
The present invention relates to a control circuit of a solenoid actuated pump, and more particularly a control circuit of a solenoid actuated pump capable of regulating an electrical energy supplied to a solenoid.
2. Discussion of the Background
There have been proposed various types of solenoid actuated pumps. FIG. 20 illustrates an example of basic arrangements of a control circuit used for the solenoid actuated pumps, in which a solenoid 8 is connected at a terminal 8a of one end thereof to a DC power, and is provided at the opposite end thereof with a switch 12 coupled to a pulse generating circuit 11 with a pulse whose ON time is invariable and ON cycle (frequency) is variable. With this arrangement, current is intermittently supplied to the solenoid 8 by operating the switch 12 in response to a pulse signal.
In accordance with a conventional control circuit of the solenoid actuated pump as described above, the range of an applicable DC power connected to the terminal 8a of the solenoid 8 and that of an applicable voltage for the pulse generating circuit 11 depend on the capacity of the switch 12. Specifically, the arrangement that the control circuit includes the switch 12 corresponding to supply voltage necessitates the replacement of an energizing circuit and a solenoid to those corresponding to a different supply voltage. Therefore, this arrangement poses a problem that various types of the control circuits are needed, thereby rendering the inventory management difficult.
In addition, as described above, the arrangement that the control circuit and the solenoid correspond to supply voltage may poses problems, for example, malfunction and burning of the control circuit caused by an improper supply voltage.
The above arrangement poses another problem that a user is required to handle various types of the pumps and control circuits, rendering the inventory management difficult and costly.
It is an object of the present invention to provide a control circuit of a solenoid actuated pump capable of eliminating a troublesome work to select supply voltage by a user for every application.